I never noticed this issue before. Sure I saw the baby watchmen, but they could be killed. Now they can't. I have to retreat my army and auto solve the fight instead, or they will kill all my men eventually.
I'm on 1.4.0 and I'm having this issue as well. I do not have the issue when I open up with steam, but I do have the issue when I open up with Vortex (even without any mods). I can load the same save file and reliably reproduce the issue based on which launcher I use. It is completely game breaking in my opinion, because any of the fighting babies are completely invincible, preventing me from attacking hideouts.
I figured out what was causing it, and a resolution for myself. It appears that I somehow re-arranged the load order in Vortex. It should be Native, Sandbox Core, CustomBattle, Sandbox, StoryMode. Since putting them back into this order, I've had no more issues with baby enemies.
If bannerlord had a fantasy element to it's theme, the role of forest bandits of short stature perfectly suits the likes of halfling rogues, gnome bandits, forest goblins, kobold outlaws, and dwarven brigands.
I wonder if modders can easily pull off replacing the faction characters with fantasy races similar to those in the first Age of Wonders, a game with a low fantasy theme, complete with moddable stats and cultural traits?